We found that administration of busulfan to mice: decreased testis weight; caused testicular
histological damage; reduced the total number of sperm, sperm motility, serum testosterone concentration;
and eventually, litter size. Preadministration of KRGE partially attenuated various busulfaninduced
damages to the male reproductive system. These results indicate that KRGE has a protective
effect against busulfan-induced damage to the male reproduction system.